a. Field of the Invention
The present invention pertains generally to land vehicle mounted dump systems and in particular to elevating and tilting dump systems for riding mowers.
b. Description of the Background
Vehicle mounted dump systems are intended to provide a way for an operator to efficiently and easily dump containers that are filled with materials. For example, a simple manual dump system for a mower may comprise a grass catcher which the operator removes manually and dumps into a trailer or truck, which transports the clippings to a landfill or compost pile.
Commercial mowers may have automated dump systems that have larger containers and powered dump systems to dump larger loads. Some existing dump systems are designed to lift the catcher and then to tilt and dump the contents while the catcher is in an elevated position.
However, existing dump systems have disadvantages that limit their productive and efficient use. For example, existing dump systems raise the catcher box so that it is maintained in a position that is substantially horizontal or parallel to the frame of the vehicle on which it is mounted. In some existing dump systems, raising the catcher box in a parallel position limits the clearance height of the catcher box making it difficult or impossible to dump the contents of the catcher into a truck or pickup that has high walls. In other existing dump systems, the catcher box is raised high, but is positioned close to the mower which can cause uneven loading and spillage necessitating extra work on the part of the operator to redistribute the dumped contents or to clean up spillage.
A parallel raised position of the catcher box with respect to the mower frame is also less desirable when the front of the mower is higher that the back of the mower, for example if the mower is parked on an incline. The can cause the clearance of the dump system to be lower with respect to a receiving vehicle that is not on the same incline.
Another disadvantage of existing dump systems is that during the elevation of the catcher box, but prior to dumping, some clippings may spill from the catcher through the catcher box door. This is more of a problem in systems which elevate the catcher box while it is maintained in a substantially horizontal position or in a position in which the catcher box tilts toward the door opening prior dumping.
Commercial lawn mowers and similar vehicles require stability in order to be operated productively and safely. Existing dump systems diminish the stability of the vehicle to which they are attached because they are mounted in a way that significantly raises the center of gravity of the combined vehicle and dump system. Dump systems that raise the center of gravity more than 4 inches may negatively affect the stability and maneuverability of the vehicle. Dump systems that raise the height of the catcher box also make transportation and storage of the vehicle difficult because of greater clearance requirements. For example, if a mower with a dump system that raises the catcher box substantially is transported or stored on flatbed truck, lack of clearance may interfere with parking and passage of the truck.
Existing systems may combine the raising and dumping motion of the dump system such that the catcher box door opens or the catcher box begins to tilt in conjunction with the raising of the catcher box. Combined raising and tilting mechanisms may cause the contents to spill or to be dumped prematurely because there is no way to control the raising and tilting functions separately.
Existing systems may also have the disadvantage that the catcher box dumping action may only occur when the catcher box is fully raised thus preventing the operator from conveniently dumping the catcher box onto the ground or onto a tarp that is placed on the ground.
Existing systems may have the disadvantage of being complicated and not well suited for field installation. Existing dump systems require professional installation equipment, personnel, and a substantial amount of time for installation making retrofitting a dump system to an existing vehicle more costly and inconvenient.